Thermostatic valve



June 12, 1934- R. J. DQUGHR'EY THERMOSTATI C VALVE Filed sept'. 22, 1932 HG. I.

Patented June 12, 1934 4UNITED STATES PATENT OFFICE THEaMosTATIo VALVE Application september 2z, 1932, serial 10.634.291

17 Claims.

My invention is applicable to control the flow of gas to a burner in accordance with the temperature of a metal part of the burner which forms one member of a thermostatic couple. In the embodiment of my invention chosen for illustration, that thermostatic member of the burner includes a Venturi tube which is mounted to reciprocate in the valve casing in coaxial relation with the stem of the valve; the latter being continually stressed toward its closed position by a spring in said casing. T hat thermostatic burner member is suspended from the valve casing by a pair of rods having a coeicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected. The opening movement of the valve against the stress of its spring is positively effected by the expansion of the thermostatic burner member. That embodiment of my invention is designed for inclusion in a water heater and is provided with a pilot burner arranged to be supplied with gas independently of the main burner supply controlled by said valve. Consequently, if 1the valve be opened to supply gas to the main burner when the pilot burner is not lighted, all the gas supplied to the main burner would be wasted and danger of an explosion incurred. Therefore, 'in said embodiment, I mount the pilot burner so that the flame therefrom heats the thermostatic member of the main burner and is effective to open the valve; so that, if the flame is accidentally extinguished at the pilot burner, when the main burner is not lighted, the main burner thermostatic member contracts and thus automatically closes the valve which controls the supply of fuel and thus prevents the waste and danger of explosion aforesaid.

My invention includes the various novel features of construction and arrangement hereinafter more definitely specified.

In the drawing, Fig. I is a front elevation of a thermostatic valve embodying my invention.

Fig. II is a vertical sectional view of said valve taken on the line II, II, in Fig. I.

Fig. III is a top plan view of the main burner shown in Figs. I and II, but in the position of Fig. II.

In said gures, the valve casing 1 has the gas inlet 2 and gas outlet passageway 3, with the partition 4 between said inlet and outlet having the port 5 extending therethrough controlled by the valve 6 which has the stem 7 mounted to reciprocate in the bearing 8 in said casing, and is continually stressed by the spring 10 toward its seat 1l on said partition, to close said port 5.

Said spring 10 abuts at its outer end against the closure plate 12 which is removably secured on said casing by the cap screws 14. The joint between said casing l and its closure 12 is rendered gas tight by the gasket 15.

I nd it convenient to form said outlet passageway 3 through the tube 16 by which said valve may be displaced from its seat in opposition to the stress of said spring 10 by the thermostatic means hereinafter described. Said casing 1 is provided with the removable closure 17 conveniently rigidly connected therewith by the cap screws 18. Said gas supply tube 16 is mounted to reciprocate, in the valve casing closure 17, in coaxial relation with said valve 6 and its stem 7, and the joint between said tube 16 and closure 17 is rendered gas tight by the packing 19 held in the stuffing box 20 by the gland 21 which has the hexagonal wrench hold 22 formed on the upper end thereof to facilitate its adjustment.

` Said gas tube 16 is adjustably rigidly connected with the Venturi tube 23. I nd it convenient to make such connection by providing said gas tube 16 with the screw thread 24 and engaging the thread 25 in the tube 23, and providing said tube 16 with the .wrench hold formed by the nut 26 which is permanently fixed on said gas tube 16 by solder or cement and providing said gas tube 16 with the lock nut 27 which may be set tight against the end of said Venturi tube 23 to hold said gas tube 16 in any desired position of axial adjustment.

Said Venturi tube 23 has air inlet openings 28 upon respectively opposite sides thereof, and is conveniently provided with the external screw thread 29 so that the effective area of said open-T' ings may be variably determined by the axial adjustment of the nut ring 30, which may be held inany desired position of adjustment by the jam nut ring 31.

Said Venturi tube 23 includes the gas and air mixing chamber 33 having the main burner head 34 at the top thereof provided with the main burner cap 35 connected therewith by the screw thread 36. As shown in Fig. III, said main burner cap 35 has two circular series of flame jet openings 37 and 38 in coaxial relation. However, it may be provided with burner orifices of any suitable form. I prefer to provide said burner cap' 35 with the baille plate 40 which -is detachably rigidly connected therewith by the screw 41, to insure thorough mixing of the gas and air and even distribution thereofto said openings.

Said Venturi tube 23 is formed of copper or.

casing closure 17 and to secure the rods-in axially adjusted position with respect to supports 45 by respective pairs of nuts 46. f' I also provide the upper ends of said rods with respective screw threads 47 but extend them through smooth holes in the respective anges 48 on said Venturi tube 23, and provide each of said rods with a pair of nuts 49 and 50 to clamp said fianges between them with the Venturi tube 23 in any desired position of axial adjustment. Said -rods are preferably formed of an alloy of ferric metal of such composition that they remain of substantially invariable length throughout the range of temperature to which they are subjected in connection with said burner. Said Venturi tube 23 and said rods 43 thus form a thermostatic couple relatively adjustable to open the valve 6 by the thrust of saidgas tube 16 to any desired extent by the expansion of said Venturi tube 23 under increment of heat; said parts being initially set, when cold, with the gas tube 16 slightly spaced above the upper end of the valve stem 7, as shown in Fig. II. Heat may be conveniently applied to said Venturi tube (to expand the latter axially and open said valve 6 to permit gas to flow from the inlet 2 to said burner openings 37 and 38) by means of the pilot burner tube 51 which is provided with the screw thread 52 at its lower end normally rigidly connecting it With the valve casing closure 17, as shown in Fig. II. Said tube 51 is in communication with the chamber 53 in said casing closure 17 through which it is supplied with gas through the duct 54 shown in Fig. II, under control of said valve 6. However, said chamber 53 may be supplied with gas through the conduit 55 which is preferably a branch of the main burner supply conduit 56 shown in Fig. II, in connection with said inlet 2 so that said pilot burner 51 maybe continually supplied with gas under control of the valve 57, regardless of whether the valve 6 is open or shut. Said pilot burner tube 51 is of the Bunsen type, being provided with the air inlet 59 vin the side thereof, as indicated in Fig. II. As indicated in Fig. II, said pilot burner tube 51 is so located that when the gas supplied thereto is ignited to form the iiame 60 at the top thereof, the Venturi tube 23 is expanded from the position shown to thrust the gas tube 16 against the upper end of the stem 7 of the valvev 6 to open the latter, but, if said llame 60 becomes accidentally extinguished, when the main burner is not lighted, the contraction of said Venturitube 23 to the position shown in Fig.

II permits said valve 6 to be automatically shut by its spring 10 to prevent the waste of gas through both the main and pilot burners and possible explosion thereof. However, if and when the valve 6 is thus automatically closed, it may be opened by the application of heat to said Venturi tube either from an external source, such as a match, or by manually opening the valve 57 and lighting the gas thus supplied, at said burners.

However, I do not desire to limit myself to the precise details of construction and arrangement herein setforth, as it is obvious that various modifications may be made therein, without departing from the essential features of my invention, as defined in the appended claims.

I claim:

1. In a thermostatic valve, the combination with a casing having a fluid inlet and .a fluid outlet, a partition between said inlet and outlet, and a valve port through said partition; of a valve for controlling said port, having a stem mounted to reciprocate in said casing; a spring, in said-casing, tending to closeL saidvalve when the structure is cool; a thermostatic couple operable to open said valve when heated to a predetermined degree, including a pair of rods vextending from said casing and composed of metal having a coeiiicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner Venturi tube formed o f metal having' a higher coeicient of expansion than said rods, rigidly connected with and supported by said rods at the ends thereof remote from said casing; said Venturi tube having 'a main burner at the end thereof remote from said casing and having a gas supply conduit for said burner extending into said casing in coaxial' relation with, but spaced away from, said valve stem when the structure is cool, said conduit being in communication with said outlet at all times; means forming a gas tight joint between said casing and gas conduit, permitting reciprocation of the latter in said casing, to and from contact with said valve stem; a pilot burner extending from said casing, on the outlet side of saidpartition, with its outlet end in position to supply a llame to normally heat said main burner to such a degree as to open said valve; whereby said valve is opened by axial movement of said gas conduit consequent upon expansion of said Venturi tube by the ame at said pilot burner and to a variable extent corresponding with the degree to which the structure is heated by flame at`said burner; the gas supply to said burner being shut ofi by said valve, when the structure is cooled and said Venturi tube contracted consequent upon the extinction of the flame at said burner.

2. A structure as in claim l, including means for `effecting relative axial adjustment of said ,rods and Venturi tube, for variably predetermining the temperatures at which said valve shall be automatically opened and shut.

3. A structure as in` claim 1, including means for effecting relative axial adjustment of said Venturi tube and gas conduit, for variably predetermining the temperatures at which said valve shall be automatically opened and shut.

4. In a thermostatic valve, the combination with a casing having a fluid inlet and a iiuid outlet, a partition between said inlet and outlet,y and a valve port through said partition; of a valve for controlling said port, having a stem mounted to reciprocate in said casing; a spring, in said casing, for closing said valve when thestructure is cool; a thermostatic couple for openingsaid valve when the structure is heated to a predetermined degree, including a rod lextending from said casing and havingl a coefficient '130 of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner tube formed of metal having a higher coeiicient of expansion than said rod, rigidly connected'with and supported 135 by said rod at the end thereof remote from said casing; said burner tube having a main burner at the end thereof remote from said casing and having a gas supply conduit for said burner ex.- a tending in said casing in coaxial relation with, 14() but spaced away from, said valve stem when the structure is cool, said conduit being in communicationwith said outlet at all times; means forming a gas tight joint between said casing and gas conduit, permitting reciprocation of the latter in said casing, to and from contact with said valve stem; a pilot burner extending from said casing, on the outlet side of said partition, with its outlet end in position to supply a flame tol normally heat said main burner to such a degree as to open said valve; whereby said valve is opened by axial movement of said gas conduit consequent upon expansion of said burner tube by the ame at said pilot burner, the gas supply to said burner being shut oif by said valve, when the structure is cooled and said burner tube contracted consequent upon the extinction of the naine at said burner.

5. A structure as in claim 4, including means for effecting relative axial adjustment of said rod and burner tube, for variably predetermining the temperatures at which said valve shall be automatically opened and shut.

6. A structure as in claim 4, including means for eiiecting relative axial adjustment of said burner tube and gas conduit, for variably predetermining the temperatures at which said valve shall be automatically opened and shut.v

'7'. In a thermostatic valve, the combination with a casing having a fluid inlet and a fluid outlet, a partition between said inlet and outlet,\ and a valve port through said partition; of a valve for controlling said port, having a stem mounted to reciprocate in said casing; a spring, in said casing, for closing said valve when the structure is cool; a thermostatic couple for opening said valve when the structure is heated-to a predetermined degree, including a rod extending from said casing and having a coecient of expansion which is substantially zero'throughout the range of temperatures to which the couple is subjected, and a burner tube formed of metal having a higher coefficient of expansion than said rod, detachably connected with said rod at the end thereof remote from said casing; said burner tube having a main burner at the end thereof remote from said casing and having a gas supply conduit for said burner extending in said casing in registry with, but spaced away from, said valve stem when the structure is cool; said conduit being in communication with said outlet at all times; means forming a gas tight joint between said casing and gas conduit, permitting reciprocation of the latter in said casing, to and from operative relation with said valve stem; whereby said valve is opened by axial movement of said gas conduit consequent upon expansion of said burner tube by flame at said burner; but the gas supply to said burner is shut oi by said valve, when the structure is cooled and said burner tube contracted consequent upon the extinction of the flame at said burner.

8. A structure as in claim 7, including means for effecting relative axial adjustment of said rod and burner tube, for variably predetermining the temperatures at which said valve shall be opened and shut by the thermostatic couple.

9. A structure as in claim 7, including means for effecting relative axial adjustment of said burner tube and gas conduit, for variably predetermining the temperatures at which said valve shall be opened and shut by the thermostatic couple.

10. In a thermostatic valve, the combination with a casing having a fluid inlet and a fluid outlet, a partition between said inlet and outlet,4 and a valve port through said partition; of a valve for controlling said port; a spring normally stressing said valve in one direction; a thermostatic couple operative'to move saidy valve, in opposition to said spring, including a rod extending from said casing and composed of material having a coefiicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner tube formed of material having a higher coeflicient of expansion, supported by said rod and having a main burner structure at the end thereof remote from said casing; a gas conduit to said burner, carried by said burner tube, and mounted to move in said casing in operative relation with said valve; said conduit being in communication with said outlet at al1 times; whereby said valve is held in one extreme position ,by its spring, when the structure is cool, and

moved toward its other extreme position by expansion of said burner tube, when the latter is heated above a predetermined degree.

11. In a thermostatic valve, the combination with aA casing having a fluid inlet and a fluid outlet, a partition between said inlet and outlet, and a valve port through said partition; of a valve, mounted in said casing, for controlling said port; a spring for moving said valve in one direction; a thermostatic couple operative to move said Valve, in opposition to said spring, when heated, including a rod extending from said casing and composed of metal having a coeflicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner Venturi tube formed' of metal having a higher coefficient of expansion, supported by said rod and having a main burner structure at the end thereof remote from said casing; a gas conduit to said burner, carried by said Ven- 'turi tube, and mounted to reciprocate in said casing in operative relation with said valve; means A forming a gas tight joint between said casing and reciprocatory member; said conduit being in communication with said outlet at all times; whereby said valve is held by its spring when the structure is cool and moved by expansion of said Venturi tube when the latter is heated above a predetermined degree;A and means for heating said Venturi tube.

12. In a thermostatic valve, the combination with a casing having a fluid inlet and a fluid outlet, a partition between said inlet and outlet, and a valve port through said partition; of a valve. mounted in said casing, for controlling said port; a spring for moving said valve in one direction; a thermostatic couple operative to move said valve, in opposition to said spring, when heated, including a rod extendingl from said casing and coniposed of metal having a coeflicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner Venturi tube formed of metal having a higher coefficient of expansion, supported by said rod and having a main burner structure at the end thereof remote from said casing; a gas conduit to said burner, carried by said Venturi tube, and mounted to reciprocate in said casing in operative relation with said valve, said conduit being in communication with said outlet at all times; means forming a gas tight joint lbetween said casing and reciprocatory member; whereby said valve is held by its spring when the structure is cool and moved by expansion of said Venturi tube when the latter is heated above a predetermined degree; and means for heating said Venturi tube, including a pilot burner for lighting the main burner. i

13. In a thermostatic valve,the combinationv with a casing having a fluid inlet and' a uid outlet, a partition between said inlet and outlet, and a valve port through said partition; o f a valve, mounted in said casing, for controlling said port; a spring for moving said valve in one direction; a thermostatic couple operative to move said including a rod extending ,from said casing and composed oi metal having a coefllcient oi.' expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner Venturi tube formed of metal having a higher coeicient of expansion, sup- '.ported by said rod and having a main burner structure at the end thereof remote from said casing; a gas conduit to said burner, carried by said Venturi tube, and mounted to reciprocate in said casing in operativer'elation with said valve;

means forming a gas tight joint between said casing and reciprocatory member, said conduit being in communication with said outlet at all times; whereby said valve is held by its spring when the structure is cool and moved by expansion of said Venturi tube when tne latter is heated above a predetermined degree; means for heating said Venturi tube, including a pilot burner supported by said casing; and means for supplying gas to said pilot burner, independently of said main burner.

14. In a thermostatic valve, the combination with a casing having a iluid inlet and a fluid outlet, a. partition between said inlet and outlet, and a valve port through said partition; of a valve mounted to reciprocate in said casing for controlling said port; a spring, in said casing, for stressing said valve to close it; a thermostatic couple operative to open said valve, including a rod extending from said casing and composed of metal having a coeflicient of expansion which is substantially zero throughout the range of temperatures to which`the couple is subjected, and a burner'Venturi tube formed of metal having a higher coefllcient of expansion, supported by said rod in axially adjustable relation with said casing, and having a main burner structure at the end thereof remote from said casing; a tubular gass conduit to said burner, carried by said Venturi tube and extending in said casing in coaxial operative relation with said valve; and means forming a gas tight joint between said casing and gas conduit, permitting reciprocation of the latter in said casing; said conduit being in communication with said outlet at all times; whereby said valve is closed, and held closed, by its spring, when the structure is cool, and opened by expansion of said Venturi tube when the latter is heated above a predetermined degree.

15. In a thermostatic valve, the combination with a casing having a fluid inlet and a fluid outlet, a partition between said inlet and outlet, and a valve port through said partition; of a valve mounted to reciprocate in said casing for controlling said port; a spring, in said casing, for stressing said valve to close it; a thermostatic couple operative to open said valve, including a rod extending from said casing and composed of metal having a coeilcient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected,

. and a burner Venturi tube formed of metal having a higher coefficient of expansion, supported by said rod in axially adjustable relation with said casing, and having a main burner structure at the end thereof remote from said casing; a tubular gas conduit to said burner, carried by said Venturi tube and extending in said casing in coaxial operative relation with said valve; means forming a gas tight joint between said casing and gas conduit, permitting reciprocation of the latter in said casing, said conduit being in communication with said outlet at all times; whereby said valve is closed, and held closed, by its spring, when the structure is cool, and opened by expansion of said Venturi tubewhen the latter is heated above a predetermined degree, and to a variable extent corresponding with the degree to which it is heated; and means for heating said Venturi tube, including a pilot burner supported by said casing.

16. In a thermostatic valve, the combination with a casing having a fluid inlet and a uid outlet, a partition between said inlet and outlet, and a valve port through said partition; of a valve mounted to reciprocate in said casing for controlling said port; a spring, in said casing, for stressing 'said valve to close it; a thermostatic couple operative to open said valve, including a rod extending from said casing and composed of metal having a coeiiicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner Venturi tube formed of metal having a higher coefficient of expansion, supported by said rod in axially adjustable relation with said casing, and having a main burner structure at the end thereof remote from said casing; a tubular gas conduit to said burner, carried by said Venturi tube and extending in said casing in coaxial operative relation with said valve, said conduit being in communication with said outlet at all times; means forming a gas tight joint between said casing and gas conduit, permitting reciprocation of the latter in said casing; where- 'by said valve is closed, and held closed, by its spring, when the structure is cool, and opened by expansion of said Venturi tube when the latter is heated above a predeterminedA degree, and to a variable extent corresponding with the degree to which it is heated; means for heating said Venturi tube, including a pilot burner supported by said casing; and means for supplying gas to said pilot burner, independently of said main burner.

17. In a thermostatic valve, the combination with a casing having a fluid inlet anda uid outlet, a partition between said inlet and outlet, and a valve port through said partition; of a valve for controlling said port; a spring normally stressing said valve in one direction; a thermo- `static couple operative to move said valve, in

opposition to said spring, including a rod extending from said casing and composed of material having a coeicient of expansion which is substantially zero throughout the range of temperatures to which the couple is subjected, and a burner tube formed of material having a higher coelicient of expansion, supportedby said rod and having a main burner structure at the end thereof remote from said casing; a gas conduit to said burner, carried by said burner tube, and mounted to move in said casing in operative relation with said valve; said conduit being in communication with said outlet at all times; whereby said valve is held in one extreme position by its spring, when the structure is cool, and moved toward its other extreme position by expansion of said burner tube, when the latter is heated above a predetermined degree; including means for heating the expansible member of the thermostatic couple, independently of the main burner. 3

'- ROBERT J. DOUGHERTY. 

